Science: Danger from Space?

From either side of the Iron Curtain, men watch the start of the space age with a sort of supranational arrogance. The human species seems about to master the solar system. The contrary may be the truth. Last week Lockheed Aircraft Corp. announced that it has a team of scientists hard at work, hoping to find a way to foil invasions of the earth that may well start from space. The invaders most to be feared will not be little green Venusians riding in flying saucers or any of the other intelligent monsters imagined by science fictioneers. Less spectacular but more insidious, the invaders may be alien microorganisms riding unnoticed on homebound, earth-built spacecraft. If they can thrive and multiply on terrestrial organic matter, it is probable that no earthly creature, including man, will be safe from their attack.

Stowaways Inside. Chief source of U.S. concern about stowaway “exobiota” (extraterrestrial life) is famed Nobel Prize-winning Geneticist Joshua Lederberg, 32, of Stanford. Lederberg is immensely nappy that the “blacksmiths” who fashion space hardware are still too clumsy to send manned expeditions to Mars or Venus. Crews that return from a foreign planet, says he, will be potential dangers to all life on earth. Though their ship may be sterilized inside and outside before re-entering the earth’s atmosphere, it will be impossible to sterilize the men themselves. Like even the healthiest humans, the space travelers will be hives of earthly viruses, bacteria and protozoa, and among these familiar and harmless companions a few microscopic aliens may hide, ready to turn into killers when they reach the earth.

Lederberg is familiar with all the reasons why nonearthly life will probably perish when exposed to an earthly environment. But he points out that earth’s scientists know only one kind of life, the familiar earthly form based on amino acids linked into protein molecules. This sort of life requires a watery environment and a narrow range of temperature. Elsewhere in the universe there may be living organisms that contain no amino acids, need no water, and can live and multiply at extremely high or extremely low temperatures. Such exobiota might do better on earth than native living creatures do. Says Lederberg: “We know that whenever two ecological systems are thrown together, the situation becomes unstable.” For a homely recent example, he points to South Pacific islanders who were virtually exterminated in the 19th century by measles, whooping cough and other diseases relatively harmless to white men.

Moon Anteater. Lederberg is working for the National Aeronautics and Space Administration on a no-return device that will look for traces of life on the moon. Carefully sterilized before launching to protect the moon from the earth’s organisms, Lederberg’s spacecraft will be a sort of mechanical anteater with a sticky tongue for licking up lunar dust and placing it under a microscope to be examined by a television camera. If the camera reports to earth that the dust contains spores that may have the power of coming to dangerous life, the first manned voyage to the moon will be equipped to keep the spores from hitching a ride to earth.

Lederberg expects his no-return lab to reach the moon about 1964; a more sophisticated package of life-seeking instruments should be landed on Mars about 1967. The worried geneticist is especially pleased to hear from the space blacksmiths that manned, two-way journeys even to the moon will be unlikely for at least a decade. By the time the first human starts home from Mars, the earth’s biologists should know enough about Martian life to keep it from damaging life on the home planet.